1. Field of Invention
Aspects of the invention can relate to a method of manufacturing a thin film transistor, a thin film transistor, a thin film transistor circuit, an electronic device, and an electronic apparatus.
2. Description of Related Art
Related art, thin film transistors using organic materials (organic semiconductor materials) presenting electrically conductive properties similar to semiconductors are being developed. The thin film transistors have advantages of being low-profile and can realize weight-saving, flexibility, low material cost and the like. Further, they can be used as switching elements for flexible displays or the like.
As such related art thin film transistors, a structure is proposed, for example, in Japanese Unexamined Patent Publication No. 5-55568, International Patent Publication No. WO0147045, and International Patent Publication No. WO0147043, in which a source electrode and a drain electrode are formed on a substrate with an organic semiconductor layer, a gate insulating layer, and a gate electrode stacked on these electrodes in this order.
Japanese Unexamined Patent Publication No. 5-55568 discloses that a vacuum deposition method is used for forming a gate electrode, a source electrode, and a drain electrode. By forming an insulating layer and an organic semiconductor layer using the vacuum deposition method in addition to forming the gate electrode, the source electrode, and the drain electrode using the vacuum deposition method as described therein, a high-performance thin film transistor can be manufactured with good reproducibility. However, the vacuum deposition method requires a large-scale facility, and presents problems of high-cost and so on derived from large power consumption required to form the films.
Meanwhile, International Patent Publication No. WO0147045 and International Patent Publication No. WO0147043 disclose that all of the gate electrode, the source electrode, drain electrode, the insulating layer, and the organic semiconductor layer are formed as films by a wet process under the atmospheric pressure.
According to this, a thin film transistor can be manufactured with a low cost. However, in the actual situation, the thin film transistors described in the International Patent Publication No. WO0147045 and International Patent Publication No. W00147043 have sufficient properties in comparison with thin film transistors manufactured by the vacuum deposition process.